Mark Pincus, Zynga

Shares of Zynga(ZNGA) plummeted by 76% this year, riding a wave of bad news. After buying game maker OMGPOP for $183 million earlier this year, Zynga wrote off half the deal's value in October, citing the rapid popularity decline of flagship game "Draw Something." The company cut 5% of its staff two months ago and slashed its 2012 outlook because of underperforming games.

That collection of woes would land any CEO on the hot seat. But getting rid of Pincus would be difficult for Zynga: He owns a special class of Zynga shares with 70 times the voting power of ordinary shares. That gives him control of around 58% of Zynga's total voting power, according to the company's latest quarterly report.

In other words, the only person who could fire Pincus is Pincus himself.